Luton have made their ninth summer signing following the arrival of winger Danny Green.
Notts County have signed Togo international Mawouna Amevor on a two-year deal.
Hearts manager Paulo Sergio has confirmed he wants to stay at the club and is holding talks regarding a new contract at Tynecastle.
Sergio replaced Jim Jefferies at the helm in August and has led Hearts to a Scottish Cup final date with local rivals Hibernian next month.
The Portuguese's contract expires at the end of the season and he is hoping that an agreement can be found for him to remain in charge.
"I want to stay. In the right moment we will see if that's possible or not," he said.
"We are speaking about that (contract talks). I'm here every single day. I don't do anything else unless living a Hearts life.
"At the moment I just eat and sleep. I didn't come here to be on holiday. I work every single minute I can. I hope we can be happy in the end."
Hearts have had numerous problems this season, not least significant salary delays during four months, most recently in March.
Sergio praised the Hearts board for easing the financial concerns, and also his players, who sit sixth in the SPL with four games to go.
He added: "We have to give credit to our players for what they did and the way they helped our board to deal with the problems.
"We shouldn't forget achieving the semi-final and the final of the cup brings a lot of joy - and some money too.
"For my players all my congratulations. But it's not finished. They should keep playing and continue like that."
Midfielder Jason Holt is set to return to the scene of his Hearts debut on Saturday after a glowing endorsement of his talent from his manager.
The 19-year-old made his debut as a substitute on the final day of the last Clydesdale Bank Premier League season at Tannadice and, as Hearts prepared for Saturday's clash with Dundee United, Sergio had nothing but praise for Holt.
Holt scored on his first start for Hearts, a 2-1 loss at St Johnstone last month.
Sergio said: "He had his opportunity, he played very well, he scored a goal, which caught the attention of everybody. He has a lot of quality but we shouldn't rush, because I believe we have a great talent there.
"He has time. He should wait for his moment and he knows.
"He's humble, a hard worker with fantastic technical ability. Different class. He's a kid that can go far in this profession."
With Hearts seeking to climb from sixth place in the SPL standings and in the Scottish Cup final, Holt may have to wait for another chance.
Sergio added: "We are playing very, very important games and it's not the kids that should take responsibility at this moment."
Holt joined Hearts aged nine, progressing through the youth ranks and was named Clydesdale Bank Under-19 Player of the Season in 2011. He was on loan at Irn-Bru First Division Raith Rovers earlier this season but is now at the sharp end of things in the top flight and knows how vital a period it is.
Holt said: "Just to feature in any game for Hearts means a lot to me but if I was to feature in the cup final or the games in the push for Europe would mean a lot to me.
"The club and all the players want to make Europe. The next few games are really crucial before the cup final.
"We're hoping to get maximum points from every game."
Hearts have stated their intention to cut costs this summer and develop youth, meaning Holt and others are likely to be given an opportunity.
He added: "Everyone knows about the club and financial matters but Hearts have always been a club that are going to promote young boys. That gives the young boys an extra chance with the financial matters."
Holt has watched with interest the development of another young midfielder this term and played alongside Scott Robinson, who is a year his senior, at McDiarmid Park.
"Scott playing quite regularly gives a boost to all the young boys," Holt added.
"I played with Scott at under-19 level as well. When I played with him at St Johnstone it was really good.
"In the future I'd like to establish myself in the Hearts first team and take it from there."