Add a note to documentation clarifying that all integers are 64-bits long.
Add a note to documentation clarifying that all integers are 64-bits long.

See: #1159 and #1152.

VirusTotal/yara,VirusTotal/yara,pombredanne/yara,hillu/yara,hillu/yara,VirusTotal/yara,plusvic/yara,VirusTotal/yara,hillu/yara,plusvic/yara,wxsBSD/yara,wxsBSD/yara,cblichmann/yara,pombredanne/yara,wxsBSD/yara,cblichmann/yara,wxsBSD/yara,plusvic/yara,hillu/yara,pombredanne/yara,plusvic/yara,cblichmann/yara,pombredanne/yara,cblichmann/yara,hillu/yara,VirusTotal/yara,plusvic/yara,pombredanne/yara,cblichmann/yara,wxsBSD/yara