Fix issue with "save" function not accepting unicode strings in Python 2.x
Fix issue with "save" function not accepting unicode strings in Python 2.x

This fix also affects external variables, now unicode strings can be passed as values for external variables.

foreni-packages/yara,pombredanne/yara,MeteorAdminz/yara,rayyang2000/yara,foreni-packages/yara,tanium/yara,smaudet/yara,wxsBSD/yara,foreni-packages/yara,kallanreed/yara,frbapolkosnik/yara,msuvajac/yara,msuvajac/yara,plusvic/yara,rednaga/yara,smaudet/yara,VirusTotal/yara,mgoffin/yara,frbapolkosnik/yara,rednaga/yara,beikezcs/yara,jpypi/yara,VirusTotal/yara,mgoffin/yara,wxsBSD/yara,pombredanne/yara,cblichmann/yara,rayyang2000/yara,plusvic/yara,jpypi/yara,hillu/yara,hillu/yara,mgoffin/yara,tanium/yara,VirusTotal/yara,plusvic/yara,jshufelt/yara,hillu/yara,neatsun/yara,smaudet/yara,MeteorAdminz/yara,jpypi/yara,kallanreed/yara,beikezcs/yara,jshufelt/yara,Security513/yara,smaudet/yara,cblichmann/yara,MeteorAdminz/yara,tanium/yara,frbapolkosnik/yara,frbapolkosnik/yara,cblichmann/yara,beikezcs/yara,bmagistro/yara,tdr130/yara,bmagistro/yara,rayyang2000/yara,plusvic/yara,wxsBSD/yara,VirusTotal/yara,tdr130/yara,msuvajac/yara,pombredanne/yara,Security513/yara,wxsBSD/yara,cblichmann/yara,mgoffin/yara,tdr130/yara,neatsun/yara,pombredanne/yara,hillu/yara,cblichmann/yara,neatsun/yara,rednaga/yara,hillu/yara,bmagistro/yara,kallanreed/yara,pombredanne/yara,wxsBSD/yara,jshufelt/yara,plusvic/yara,VirusTotal/yara,Security513/yara,jshufelt/yara