fix usage to change "python2" to "python"

Our the ID scripts have long been refactored to use Python3 over Python2 but the usage was not fixed to reflect this. This commit fixes the usage statement

Author: owlang

DeletionID/delScripts/detect_deletion_BAM.py

@@ -15,7 +15,7 @@
 Log2 output minimum threshold (Default -3)		-l Log2_Threshold
 Mappability threshold to consider (Default 0.25)	-M Mappability_%
 
-Example: python2 detect_deletion_BAM.py -b NGS.bam -c Interval.bed -m Mappability.tab -o NGS_deletion.tab -l -2 -M 0.25
+Example: python detect_deletion_BAM.py -b NGS.bam -c Interval.bed -m Mappability.tab -o NGS_deletion.tab -l -2 -M 0.25
 """
 
 def calculateDeletion(PASS):

EpitopeID/epiScripts/calculate_EpitopeSignificance.py

@@ -6,7 +6,7 @@
 This script takes in the paired-end table containing the stats from the EpitopeID pipeine and calculates
 the Poisson p-value threshold given a minimum 2-fold enrichment over the expected tags based on the bin size.
 
-Example: python2 calculate_EpitopeSignificance.py -t PE_table.out -p 0.05 -c 10000 -s 12000000 -o PE_sig.out
+Example: python calculate_EpitopeSignificance.py -t PE_table.out -p 0.05 -c 10000 -s 12000000 -o PE_sig.out
 """
 
 # Main program which takes in input parameters